Air cleaner and silencer assembly



June 30, 1942. H. a. KAMRATH 7,

AIR CLEANER AND SILBNCER ASSEMBLY I Original Filed Sept. 25, 1935 .3Sheets-Sheet 1 3mm A H. G. KAMRAT H AIR CLEANER AND SILENCER ASSEMBLYJune 30, 194 2.

Original Filed Sept. 25, 1955 5 Sheets-Sheet 2 3 Sheets-Sheet 3 H. G.KAMRATH AIR CLEANER AND SILENCER ASSEMBLY Original Filed Sept. 25, 1935jib I IHIIII II IH.

June so; 1942.

' Patented June 30, 1942 UNITED STATES. PATENT OFFICE Herbert GnKamrath,Flint, Mich, assignor to General Motors Corporation, Detroit, Mich., acorporation of Delaware Application September 25, 1935, Serial No.41.999

Renewed July 18, 1940 25 Claims. (Cl. 183-15) parts of a bafie which isincorporated in the air This invention relates to apparatus for removingforeign matter from gases and to assemblies of such apparatus withapparatus for attenuating sound waves in the gases and, moreparticularly,

to air cleaners and air cleaner and silencer assemblies for use inconjunction with carburetors of internal combustion engines.

In one of its aspects, the invention resides in air cleaners which areparticularly adapted for use in localities inwhich there is in the air alarge amount of foreign matter which must be removed before the air isfit for introduction into an internal combustion engine. Such aircleaners must, without offering undue resistance to the passage of air,be capable of removing large quantities of foreign matter from it overextended periods of time without any attention or care. An object ofthis invention in this respect is to provide air cleaners with thementioned characteristics and capabilities which may quickly and easilybe disassembled and reassembled when it becomes necessary to cleanthem.-

More specifically, in the aspect which has been discussed, the invention.resides in liquid bath type air cleaners and has for an object toprovide air cleaners of this type in which there may be maintained asupply of liquid adequate to insure that the filter will be kept wettedand washed and an effective settling pool for foreign matter removedfrom the air by the air cleaners without danger of liquid being carriedbeyond the air cleaners by the air or lost by weltering.

In the other of its aspects, the invention resides in assemblies of aircleaners andsilencers and has for its principal object to provideassemblies of liquid bath type air cleaners and resonator type silencerswhich areeflicient, compact and neat in appearance.

For a betterunders'tanding of the nature and objects of this invention,reference is made to the following specification wherein there aredescribed the embodiments of the invention which are illustrated in theaccompanying drawings, in

which:

Fig. 1 is a side elevation of an intake silencer and air cleanerassembly with parts broken away and in section.

Fig. 2 is an enlarged view, partly in elevation and partly in section,of theair cleaner included in the assembly shown in Figure l.

Fig. 3 is a'fragmentary bottom plan view of the air cleaner shown in thepreceding. figures with parts broken away.

Fig. 4 is an exploded perspective view of the manner to the air cleanercover i2.

buretor. an opening in its lower face aroundwhich is secleaner shown inthe preceding figures.

Fig. 5. is a' view, partly in elevation and partly in section, ofanother intake silencer and air cleaner assembly.

Fig. 6 is a fragmentary vertical section through a modified form-of theair cleaner shown in the preceding figures.

Fig. 7 is a perspective view of a baiiie incorporated in the air cleanershown in Fig. 6.

An assembly of an intake silencer 2 of the resonator type and an aircleaner designated generally'by the reference character A is shown inFig. 1 of the drawings. At the end opposite that attached to the aircleaner, the silencer is provided with a circular split flange E forattachment to the air intake tube of a downdraft car- The left-hand endof the silencer has cured a split flange 8 into which fits a shorthollow cylinder Hi which is secured in any suitable split flange 8extends a split clamping ring it which is pulled by a screw ll tightlyaround the der Ill.

'extremity, a cup-shaped outer casing The air cleaner 4 has, at itscenter; a hollow cylinder l6 to which is secured, near its lower t8, thecylinder projecting through the base of the casing for a short distance.the casing has a series of air louvres 20, throughout its circumference,for the intake of air. Near its lower part the vertical sidewall of thecasing is stepped inwardly as indicated at 22 for a pur- -pose whichwill become evident as the description inner edge to about half way toits ,outer edge,

certain of these openings 30 being extended by slots 32 farther towardthe outer edge of the wall 28 to join with arcuate openings 34 near theouter edge of the wall 28'. The upper wall 26 of the filter member hasin it a circumferential series of radial openings which are similar tothe openings 30 but extend from near the inner to near the outer edge ofthe wall. These upper Around the r The upper portion of .and lower wallsof the filter member are connected by two cylindrical members 36 and 38which form the inner and outer walls of the filter the upper edge of theside wall .of the casing I8.

Thus the filter member is supported at its outer edge by the casing I8and at its inner edge by the cylinder IS with its lower wall 28 wellabove the bottom of the casing IS.

Secured within the central opening in the upper wall 26 of the filtermember is a member 48 which is fiaredoutwardlyabove the upper wall theair cleaner from carrying liquid beyond it and also serves toprevent theair passing through the inner portion of the filter member to theexclusion of the rest of it.

The cover portion H of the air cleaner has a peripheral bead 50 formedtherein which carries a' sealing gasket 52 which is seated on the outeredge of the flange 486 on the upper wall of the filter member. Thus whenthe air cleaner is totally assembled with the top in place and the sameis applied to the intake silencer'2, as described in the earlier part ofthe specification, the whole is clamped together by a long rod 54 whichextends through the upper wall of -the intake silencer 2 and downthroughthe central tube l6 0! the air cleaner as best shown in Fig. 2.The lower end of the cylinder it which, as has been said, projectsslightly through the bottom of of the filter member to a point wellbeyond the I inner edges of the slots in it. The member 48 acts as abaflle to prevent the air passing through the casing I8 is closed by acircular cap 56in which is secured a member 58 through which the 'rod 54also extends. Between the lower end of the membe'r 58 and the head onthe lower end of the rod 51 is clamped'one ,end of'a bracket 60 for.supporting the air cleaner and silencer as- 'sembly. The opposite end ofthe rod 54, which extends through the upper wall oi'the intake silencer2, is threaded and a thumb nut 62 is applied thereto to pull thepartstightly together. Before the assembly shown in Figure l is put intouse, the reservoir defined by the center tube l6 and the casing l8 oithe aircleaner is filled;

with oil or some other suitableliquid 64 to about the level indicatedinthe drawing and the filter material 66 .is wetted with the {same'liquid. When the assembly is in use, air enters it through the louvres20, passes downwardly through the passage between the outer wall 38 ofthe filter member and the side wall of the casing 18, around the lowerouter edge of. the filter member through the openings 30. The-air thenpasses through the filter material 66, out of the filter member throughthe openings in its upper wall 26 whence it passes through thetubular'member l0 into the silencer 2 and thence through 'the openingencircled by the flange 6 into the'carburetor and cylinders of theengine on which the assembly isinstalled. In the course of its travelfrom the passage between the outer =wall of the filter member and theside wall of the casing into the interior of the filter member, the-airand into the interior of the filter member strikes the surface of theoil in the reservoir,

1 filter material.

'of the air cleaner.

deposits some of the foreign matter carried by it in the oil and picksup some of the oil and carries it with itinto the filter material. Theforeign matter which remains in the air and the oil picked up by the airare extracted from the air by. the filter material and, consequently,the air which leaves the filter member is free of foreign matter andoil. The silencer 2, of course, suppresses the intake noise of theengine on which the assembly-is installed and, thus, the assembly shownin Figure 1 cleans the air which enters the engine and eliminates itsintake noise.

The oil which is carried into the filter member by the air iscontinuously returned to the reservoir through the openings 34, carryingwith it the foreign matter extracted from the air by the This foreignmatter settles to the bottom of the reservoir and is thus removed fromthe field of action. Thus while the air cleaner is in use the filtermaterial is continuously washed and kept wetted and the foreign matterextracted from the air by the air cleaner disposed at. I

To'the lower outer edge of the filtermember there'is suitably secured abattle 68 which curves downwardly to a point opposite the edge of thestep in the side wall of the casing I8 and then inwardly to a point wellbeyond the openings 34 in the lower wall of the filter member. Thebaiile 68 has several functions. It reduces the cross sectional area ofthe passage through which air travels from the passage between the outerwall of the filter member and the side wall of the casing l8 into theinterior of the filter member and thus increases the rate of fiow of airand reduces the pressure at this point. The increase in rate of flow ofair has the effect of increasing the 'force with which the air impingesagainst the surface of the oil in the reservoir and, consequently, theamount of dirt depositedby the air in the reservoir and the amount ofoil picked up by the air. The reduction in pressure has the effect ofincreasing the rate-of return of oil from the filter member to thereservoir through the openings 34. The bailie (SB-also serves to shieldthe openings 34 from the entrance of air and thus to increase theirefiiciency as paths for the return of oil from the filter member to. the1'eser-.

Since it is'desired to use the air cleaner under varyingconditions andwith various types and sizes of motors, it is advisable to provide somemeans for limiting and changing the action of the air and the oil andairin the various parts If the air cleaner is to be used on anexceedingly large motor, the velocity of mean fiow will be very high andtoo much of the oil in the sump will be carried up into the filteringmaterial. Also, if the air cleaner is to be used on a truck overexceedingly rough ground, it might be possible for some of the oil inthe sump to be thrown out through the air intake louvers due tomechanicalvibration.

In order to overcomethese difiiculties and to give a more flexible unitto be used with various installations, a battle has been provided whichmay be applied to the unit already described or omitted depending on theinstallations. This baiile consists of a member 12 which is imperiorateand a member ID which is riddled with perforations. The member 12 isring-like in form and angle-shaped in cross section with spring fingersl8 projecting from the upper edge of its steeply upwardly and outwardlyinclined wall. The member 10 is in the form of a' gently inends thereof.

clined frusto-cone and has its outer edge suitably secured to the inneredge I6, of the gently upwardly and inwardly inclined wall of the member72.

The balile 12-10 is disposed within the casing I8 around the center tubeI6 and between the filter member and the bottom of the casing with belowthe baflie-shields the portion of the oil below it from the airtraveling through the air cleaner and also inhibits weltering of the oilin the reservoir. The portion of the oil below the baiile constitutes apool into which foreign matter extracted from the-air bythe air cleanermay settle out of reach of the air traveling through the air cleaner.The supply of oil above the baille is renewed from the portion of theoil below the baflie by flow over the inner edge of the member I2 and byreturn ofoil from the filter member through the openings 34 and over thebattle 68, beyond which the gently upwardly and inwardly inclined wallof the member I2 projects. Only from the portion of the oil above thebaille can the air'traveling through the air cleaner pick up oil and,consequently, the possibility of the air picking up too much oil iseliminated.

the upper end of the intake silencer is shown at 8|] having a centraltube 82 concentric within an outer shell 84. The two areconnectedtoannular plate 86, the edges being flanged together to form aninterconnection between the plate 86 and the outer shell 84 and thecenter tube 82 being connected with the plate 88 by welding. This plate86 also supports, above the cylinder 82, an inverted U-shaped bracket 88which is connected thereto by rivets 88 at the The construction of theair cleaner as a whole inthis instance is substantially the same as thatset forth in the previous modification with these exceptions: the lowerend of the center tube I6 does not extend through the base of the casingI8; there is no air outlet opening in the cover I2; the lower end of thecenter tube I6 is open; and the baflle 68' which corresponds to thebaiile 68 is riddled with perforations whose efiect is to reduce thevelocity of travel of air from the passage between the outer wall of thefilter member and the side wall of the casing I8 into the filter member.Further reduction of the velocity of travel of air at this point, whichmay be desirable'if theair cleaner is to be used on an engine whichrequires .a very large quantity of air, may, of course, be effected bycomplete elimination of the bafile.

The air cleaner is seated on the upper end of the silencer with itscenter tube aligned with the center tube of the silencer through theintermediary of a gasket I88 which serves to pretop of the silencer andthe bottom of the air cleaner. The air cleaner is secured to thesilencer and the gasket I88 compressed by an elongated thumbscrew 94which extends through the cover I2 and the center tube I8 and isthreaded into ,a member 98 carried by the U-shaped bracket 88.

The modification shown in Figure 5 lends itself to a very compactassembly between the intake silencer and cleaner in that the two areconcentric and substantially a single unit with no elbow support asshown in the first form.

The assembly shown in Figure 5 was designed for'installation on aninternal combustion engine equipped with a downdraft carburetor with thelower end of the center tube of the silencer connected to the air intaketube of the carburetor. In general this assembly operate in the samemanner as that shown in Figures 1 to 4 and it is, consequently, deemedunnecessary to describe its mode of operation further than to point outthat in it air leaves the air cleaner through the center tube I6,instead of through the cover, whence it passes into the upper end of thecenter tube 82 of the silencer and thence through the center tube of thesilencer into the,

carburetor and cylinders of the engine on which I84, thelatter beingslightly flared over, as

shown at I08, to rest on top of the bead for support. The baflie'then istapered slightly inward and has a plurality of legs IIU extendingdownwardly which engage the'lower corner of the filter assembly 24 forsupport on the lower end. The body of the member I84 is periorated asshown at III, to allow air passage therethrough.

The air cleaner shown in Figures 6 and 7 does not difier from that shownin Figure 5 except in the mentioned respects,- in that the baffie whichcorresponds to the baflle 68 is imperforate and in that an invertedU-shaped bracket H3 is supported on the inner surface of the cylinder I6to secure the top on the casing by a bolt I III and a wing nut H8. Thebafile Ill l operates very sat isfactorily to prevent any oil splashingfrom the sump 84 up and out of theannular passage between the filterelement and the casing I8. The skeleton construction of-the lower end ofthis bafile also prevents whatever oil passes through these perforationsand any dust entering the louvres from accumulating between the bafilcand the filter element.

I claim:

1. In an air cleaner, an outer casing, a filter 3 assembly supportedthereon but spaced from the casing to form an annular air passage, abaliie comprising a ring shaped member, a truncated dished cone securedto the ring member and a plurality of legs projecting from the ring intothe space betwen the filter assembly and the casing to support thebaiile below the filter assembly.

2. In an air cleaner, a large drum shaped casing having an oil bath inthe base, a central tube supported in the casing, a filter assemblysupported between the" central tube and the casing and forming with theouter casing an annular air passage through which the air may fiow downto the oilbath, a circular indented bead on the cas- 4 ing adjacent thelower edge of the filter assembly whereby the two form a restrictedpassage, a circular inwardly curved baflle secured to the filter atthispoint to direct the air out over the oil bath and a cone shaped bafliehaving supporting legs extending into the restricted portion for holdingit over the oil bath to prevent excessive quantities. from being carriedup into the filter.

A 3. An air cleaner comprising, a large drum shaped casing having an oilpool in its base, a

central cylindrical tube supported in the center of the casing, anannular filter assembly supported between the two and spaced from theouter casing to form a vertical air passage, and a perforated annularring baflle supported in the air'passage between the-side wall ofthe'filter assembly and the side wall of the casing to pre; vent the oilfrom splashing out of the base of the casing.

4. In an air cleaner, a large drum shaped casing, a central tube whichis connected to and extends upwardly from the bottom of the casing,.

an annular filter assembly including an annular top plate extending onboth its inner and outer edges beyond the body of the assembly, flangeson both the inner and outer edges of the mentioned top plate adapted toengage the; upper rim of the tube and the casing, respectively, tosupport the filter assembly, and a' gasket between the top of the tubeand the inner flange on the top plate.

5. In an air cleaner, 9. large drum shaped casing having an oil pool inits base, a central cylindrical tube supported in the center of thecasing,

an annular filter assembly supported between the two and spaced from theouter casing to form a vertical air passage, and a perforated annularbattle in the shape of a truncated cone supported in the air passagebetween the side wall of the filter assembly and the side wall' of thecasing and extending from the casing to the filterv assembly,

' 6 In an air cleaner, 9. generally cup-shaped body, a generally'tubularelement which is conside wall of the former and provided with springfingers which engage the latter. 4

9. In. an air cleaner, a generally cup-shaped body, a generally tubularelement which is connected to and extends upwardly from the bottom ofthe generally cup-shaped body and defines therewith an annularreceptacle, an annular filter element disposed within the annularreceptacle and spaced from the side and: bottom walls of i the generallycup-shaped .body; and a generally -frusto-conical bafile riddled withopenings which extends between the side wall of the generally cup-shapedbody and the side wall of the annular filter element and is providedwith spring fingers which maintain it in position.

10. In an air cleaner, a generally cup-shaped body, a generally tubularelement which is connected to and extends upwardly from the bottom ofthe generally cupshaped body' and defines therewith an annularreceptacle which constitutes a liquid -reservoir,'a hollow annularmember disposed within the annularreceptacle and spaced from the sideand bottom walls of the generally cup-shaped body, openings in the lowerwall of the hollow annular member near its inner and outer edgesconnected by radially extending openings with smaller dimensionscircumferentially of the hollow annular member,

.and dust-collecting material within the hollow annular member.

11.-In an air cleaner and silencer assembly, a silencer which consistsof a generally vertically disposed shell, a wall which closes the upperend nected to and extends upwardly from the bottom of the generallycup-shaped body and defines therewith an annular receptacle whichconstitutes a liquid reservoir, an annular filter element disposedwithin the annular receptacle and spaced from the side and bottom wallsof the generally cup-shaped body, and an annular bafiie riddled withrelatively small perforations which is carried by and dependsfrom theouter wall of the annular filter element and terminates short of thebottom of the generally cup-shaped body.-

of the shell, and a generally tubular element which extends through thespecified wall and the interior of the shell; an air cleaner whichconsists of a generally vertically disposed generally 7. In an aircleaner,- a generally cup-shaped 7 body, aigenerally tubular 'elementwhich is connected to and extends upwardly from the bottom of thegenerally cup-shaped body and'defines therewith an annular receptaclewhich constitutes a liquid reservoir, an annular filter element disposedwithin the annular receptacle and spaced from the'side and bottom wallsof the generally cup-shaped body, and an annularbaflle which issupported by the generally cupcup-shaped body mounted on the upper endof the silencer element, a cover therefor, and a generally tubularelement which is connected to the bottom of the generally cup-shapedbody and is approximately alined with the first-specified generallytubular element; a sealing gasket which is interposed between the bottomof the generally cupeshaped body of the air cleaner and the upper endwall of the silencer and encircles the duct defined-by the specifiedgenerally tubular elements, and an element which extends through thecover and the generally tubular element of the air cleaner and isconnected to the silencer to comshaped body between its bottom and thebottom of the annular filter element and extends from the side wall ofthe generally cup-shaped body toward the generally tubular element withits outer and inner edges above and an interme diate portion of it belowthe liquid level in the cup-shaped body.

press the gasket and secure the air cleaner and the silencer together.

12. In an air cleaner, a generally cup-shaped body, a generally tubularelement which is connected to and extends upwardly from the bottom ofthe generally cup-shaped body and defines with it an annular receptaclewhich constitutes a liquid reservoir, an annular filter element disposedwithin the annular receptacle and spaced I from the side and bottomwalls of the generally cup-shaped body, and an annular bafile which issupported by the generally cup-shaped body be tween itsbottom and thebottom of the annular filter element and extends downwardly and thenupwardly from the side wall of the generally cupshaped bodytoward thegenerally tubular element and is imperforate near its outer edge andriddled with relatively small openings inwardly thereof.

" ried by and depends from the outer wall of the annular filter elementand is inclined in the direction of the generally tubularelement andterminates short of the bottom of the generally cupshaped body, and anannular baflie which is supported by the generally cup-shaped bodybetween its bottom and the bottom of the annular filter element andextends from the side wall of the generally cup-shaped body toward thegenerally tubular element with its outer edge above and a portion of itbelow the liquid level in the generally cup-shaped body.

14. In an air cleaner, a generally cup-shaped body, 'a generally tubularelement which is connected to and extends upwardly from the bottom ofthe generally cup-shaped body and defines with it an annular receptaclewhich constitutes a'liquid reservoir, an annular filter element disposedwithin the annular receptacle and spaced from the side and bottom wallsof the generally cup shaped body, a generally frusto-conical baflieriddled with openings which extends between the side wall of thegenerally cup-shaped body and the side wall'of the annular filterelement, and an annular baflle which is carried by and depends travelupwardly from the surface of the liquid in the reservoir toward the airoutlet orifice,

means in the last mentioned passage to remove from the air which travelsthrough it foreign matter and liquid picked up by the air from thesupply in the reservoir, the generally bowl-shaped member having in it,in the path of travel of air toward the surface of the liquid in thereservoir,

' a circular shelf which is disposed below the static level of liquid inthe reservoir but above the bottom of the generally bowl-shaped member,and a baffle which is riddled with perforations extending upwardly andin the direction of travel of air through the air cleaner from the edgeof the shelf.

1'7. In an air cleaner, air inlet and outlet orifices, a generallybowl-shaped'member which constitutes a liquid reservoir, a generallycylindrical member disposed within the generally bowlshaped member andspaced from the side and lower walls thereof to define a passage throughwhich air may travel downwardly from the air 'inlet orifice toward thesurface of the liquid in the reservoir and a passage through which airmay travel upwardly from the surface of the liquid in the reservoirtoward the air outlet orifice, means in the last mentioned passage toremove from the air which travels through it foreign matter and liquidpicked up by the air from the supply in the reservoir, and a circularbaffle which extends upwardly in the direction of travel of air throughthe air cleaner from a point below to a point above the static levelof'liquid in the reservoir and has an imperforate portion below and aportion riddled with perforations above the static level of liquid inthe reservoir.

18. In an air cleaner, air inlet and outlet orifices, a generallybowl-shaped member which from the outer wall of the annular filterelement and is inclined in the direction of the generally tubularelement and terminates short of the bottom of the generally cup-shapedbody.

15. In an air cleaner, a generally bowl-shaped member, a generallytubular member which is connected to and extends upwardly from the lowerwall of the generally bowl-shaped member and with it defines an annularreceptacle which constitutes a liquid reservoir, an annular filtermember with air inlet and outlet orifices in its lower and upper wallsdisposed within the generally bowl-shaped member with its outer side andlower walls spaced from the side and lower walls of the generallybowl-shaped member to define a passage through which air may travel fromthe atmosphere toward the surface of the liquid in the reservoir andthence into the air inlet orifice in the filter member, the generallybowl-shaped member having in it in the path of travel of air toward thesurface of the liquid in the reservoir, an annular shelf which isdisposed below the static level of liquid in the reservoir but above thebottom of the generally bowl-shaped member, and a baffle which isriddled with perforations extending inwardly and upwardly from the inneredge of the shelf toward the center of the air cleaner.

16. In an air cleaner, air inlet and outlet orifices, a'generallybowl-shaped member which constitutes a liquid reservoir, a generallycylindrical member disposed within the generally bowlshaped member andspaced from the side and lower walls thereof to define a passage throughwhich air may travel downwardly from the air inletorifice toward thesurface of the liquid in the reservoir and'a passage through which airmay constitutes a liquid reservoir, a generally cylindrical memberdisposed within the generally bowl-shaped member and spaced from theside and lower walls thereof to define a passage through which air maytravel downwardly from the air inlet orifice toward the surface of theliquid in the reservoir and 'a passage through which air may travelupwardly from the surface of the liquid in the reservoir toward the airoutlet orifice, means in the last mentioned passage to remove from theair which travels through it foreign matter and liquid picked up by theair from the supply in the reservoir, the generally cylindrical memberhaving a portion through which air may pass from the first mentionedinto the last mentioned passage projecting below the last mentionedmeans.

19. In an air cleaner, a generally bowl-shaped member which constitutesa liquid reservoir, a

' filter member with air inlet and outlet orifices in it disposed withinthe generally bowl-shaped member with its outer side and lower wallsspaced from the side and lower walls of the generally bowl-shaped memberto define a passage [through which air may travel from the atmospheretoward the surface of the liquid in the reservoir and thence into theair inlet orifice in the .filter member, and means through which air maypass disposed in the mentioned passage between the side wall of thefilter member and the side wall of the generally bowl-shaped memher toprevent liquid splashing out of 'the.,,reservoir therethrough.

20. In an air cleaner and silencer assembly, a generally verticallydisposed-shell which constitutes an element of a silencer, a generallybowlshaped member which constitutes an element of an air cleaner and acover for the upper end of the generally vertically disposed shellmounted on the generally vertically disposed shell at its periphery andsecured to it, a duct through which air is conducted from the aircleaner into the generally vertically disposed shell and through thegenerally vertically disposed shell includinga generally tubular memberwhich is connected to and extends upwardly from the lower wall of thegenerally bowl-shaped member. and with it defines an annular receptaclewhich constitutes a liquid reservoir, an annular filter member with airinlet and outlet orifices init disposed within the generally bowl-shapedmember with its outer liquid in the reservoir but above the bottom ofthe generallybowl-shaped member.

- 23'. In an air cleaner, air inlet and outlet orifices, a generallybowl-shaped member which constitutes a liquid reservoir, a generallycylindrical member disposed within the. generally bowl-shaped memberand-spaced fromthe side and lower walls thereof to define a passage sideand lower walls spaced from the side and lower walls of the generallybowl-shaped member to define apassage through which air may connected toand extends upwardly from thelower wall of thegenerally'bowl-shapedmember and with it defines an annular receptaclewhich constitutes a liquid reservoir, and an annular filter member withair inlet and outlet orifices in its lower and upper walls disposedwithin the generally bowl-shaped member with its outer side and lowerwalls spaced from the side and lower walls of the generally bowl-shapedmember to define a passage through which air maytravel from theatmosphere toward the surface of the liquid in the reservoir and thenceinto the air inlet orifice in the filter member, the generallybowl-shaped .member having in it in the path of travel of air toward thesurface of the liquid in the reservoir an imperforate annular shelfwhich is disposed below the static level of liquid in the reservoir butabove the bottom of the generally bowl-shaped member,

22. In an air cleaner, air inlet and outlet orifices, a generallybowl-shaped member which constitutes. a liquid reservoir, a generallycylindrical member disposed within the generally bowl-shaped memberand'spaced from the side and lower walls thereof to define a passagethrough which air may travel downwardly from the -air inlet orificetoward the surface of the liquid inthe reservoir and a passage throughwhich air may. travel upwardly from the surface of the liquid in thereservoir toward the air. outlet orifice, and means in the lastmentioned passage to remove from the air which travels through itforeign matter and liquid picked up by the air-from the supply inthereservoir, the generally bowl-shaped member having mm in the path oftravel of air toward the surface of the liquid in the reservoir animperforate circular shelf which is disposed below the static level ofthrough which air may travel downwardly from Y the air inlet orificetoward the surface of the liquid in the reservoir and a passage throughwhich air may travel upwardly from the surface of the liquid in thereservoir toward the air outlet orifice, means in the last mentionedpassage to remove from the air which travels through it foreign matterand liquid picked up by the air from the supply in the reservoir, thegenerally bowl-shaped member having in it in the path of travel of airtoward the surface of the liquid in the reservoir an imperforatecircular shelf which is disposed below the static level of liquid in thereservoir but above the bottom of the generally bowl-shaped member, anda baflie extending upwardly and in the direction of travel of airthrough the air cleaner from the edge of the shelf,

24. Inan air cleaner, air inlet and outlet orifices, a generallybowl-shaped member which constitutes a liquid reservoir, a generallycylindrical member disposed within the generally bowl-shaped member andspaced from the side and lower walls thereof to define a passage throughwhich air may travel downwardly from the air inlet orifice toward thesurface of the liquid in the reservoir and a passage through which airmay travel upwardly from the surface of the liquid in the reservoirtoward the air outlet orifice, means in the last mentioned passage toremove from the air which travels through it sembly from the head sothat it defines thereforeign matter and liquid picked up by the air fromthe supply in the reservoir, and a circular bafljle which extendsupwardly in the direction of travel of air through the air-cleaner froma point below to a point above the static level of.' liquid in thereservoir and has animperforateportion below the static level ofliquidin the reservoir.

a head secured over one end of the shell, a duct which includes atubular member through which air is conducted into the shell and whichis secured in and opens through the head, anannular member disposed overthe head with the orifice in it aligned with the tubular member and itsinner edge spaced lengthwise of the aswith a continuation of the ductand recess which opens into it throughout its circumference, anda filtermember through which air passes into the duct through the orifice in theannular member mounted on the annular member.

' HERBERT G; KAMRATH.

